1. Field of Invention
This invention generally relates to a method and apparatus for producing artificial rocks, specifically from expended thermoplastic containers.
2. Prior Art
Millions of thermoplastic containers are produced each year, used once, and thrown away. This creates an environmental problem as these containers are non-biodegradable and fill up an ever decreasing landfill space.
The present invention enables the conversion of such used containers into articles of renewed utility and thus enables an economically sound solution to the problem of waste disposal while at the same time, providing a valued new article, specifically a lightweight, artificial rock.
When these rocks are installed on a substrate and mortar is put between them, they look like real rocks; with differing elevations out from the substrate, and different shades, shapes, textures, and sizes. This is completely different from mold-formed, uniform rocks.
Prior art discloses various attempts to recycle used materials, and to make artificial rocks from various materials, including concrete and plastics, but they all look like they come from a cookie cutter.
U.S. Pat. No. 4,678,617 (1987), to Sykes proposes converting two-liter soda bottles into building blocks. This produces a cookie cutter effect, as all the objects are the same size and shape. This process only uses, and so is limited to, soda bottles. Also, this would not be suitable for producing artificial rocks which would need to be of different shapes and sizes to appear real.
U.S. Pat. No. 5,543,100 (1996) to Kluh and Precht proposes to manufacture large scale artificial rocks from plastic reproductions. This would involve having to go to the sites to get the molds for the reproductions, and it does not address recycling.
U.S. Pat. No. 5,911,927 (1999), to Roberts proposes a method of producing artificial rock formations using flexible molds of latex. This entails having to first make master models, and then to make the actual molds, and does not address recycling.
U.S. Pat. No. 6,132,820 (2000), to Callahan proposes to make simulated rock from Portland Cement, Bentonite or Lime, polystyrene and water, poured into removable forms. This again, involves the use of molds and does not address recycling.